Definition of Invention
The most familiar definition of the rhetorical canon of invention is the discovery of arguments. As the first of the rhetorical canons, invention is the first step in rhetorical production. Rather than being a static process, invention continues throughout the process (Lyon, 2002). Invention serves as the means by which ideas are generated, and as such, invention is defined as much by the possibility of producing ideas as the actual production of ideas (Lyon, 2002).

Competing Definitions
Writing in “Rhetoric and Hermeneutics: Division through the Concept of Invention” Lyon (2002) notes the definition of invention has become problematic due to postmodernism’s “suspicion of agency, origins, form, and progress, and its emphasis on multiple discourses, deconstruction, irony, fragmentation” (p. 37). Through an examination of hermeneutics, Lyon (2002) offers the definition of interpretative invention as invention which mediates between the reader and the text. In this view of invention, the reader can either refer to the audience or the reader who is the interpreter of the text (Lyon, 2002). Lyon (2002) argues that by defining invention as interpretative invention recognizes an awareness of the audience while the more traditional definition of invention, those strategies used by the rhetor to generate ideas and arguments, are also recognized and acknowledged. Lyon (2002) also offers that invention should be viewed or defined as that which constructs the discursive world. In "What Can Automation Tell Us About Agency?" Carolyn Miller (2007) offers another definition of invention. Miller (2007) describes invention in terms of agency, stating that agency is not only invention, but that it is the power of the rhetor.

Further Sources
For a great listing of sources on invention, please visit Rebecca Moore Howard's bibliography.

References
Lyon, A. (2002). Rhetoric and hermeneutics: Division through the concept of invention. In Atwill, J. M and Laure, J. M. (Eds.), Perspectives on Rhetorical Invent(pp. 36-52). Knoxville: University of Tennessee Press.

Miller, C. (2007). What can automation tell us about agency? Rhetoric Society Quarterly, 37, 137-157.